TV/VCR/Stereo Troubleshooting/LCD tv auto shut down


QUESTION: Question, I have a proscan LCD that as soon as any picture shows up the tv automatically shuts down. It does this as soon as a picture from the antenna, dvd or xbox comes on the tv. I have disconnected various boards and what I have discovered is that when I disconnect the FPC cable from the T-Con the tv stays on. There are two FPC cables and I have tried leaving one connected but as long as any FPC cables are connected the tv automatically shuts down the moment a picture signal reaches the tv. I can work the tv menu on the tv as long as there is no signal input. Does this mean the T-Con board is junk or could there be other possibilities?

ANSWER: I would try replacing the T-con board; they are known to be troublesome and are usually not expensive.

Before replacing it google the model number of your set and see if others on forums and fixya sites have had the same trouble.

A general comment:  Proscan sets are not known for their reliability.  If the set is getting a little older, say over 3 years of age, you may find it a wiser investment to replace it with a new model of a different brand.

If you do need more help I must have the model number so I can look it up and review its history.


---------- FOLLOW-UP ----------

QUESTION: ProScan 40ld45q

I picked this up for free at a yard sale to tinker with.  As a hobby I enjoy learning about electronics.  I was going to try and find some schematics on the boards so that I could test the boards.  Would you know where I might find schematics for these boards.  The Mainboard is t.zr39772.7a / ms-1e198407; the T-Con is v400h1-c01 and the power board is AYL400201.  I have been searching the Internet for this but no luck yet.


There may be some hints in the above links that are good for your guidance.

Finding schematics for the actual circuit boards is very difficult.  Generally, the only place to find them is from the manufacturer and they charge $$$ for them.  

Some manufacturers don't even provide schematics at all as their official repair and training programs are centered around replacing the various boards and connectors.

Based on my quick google research your set's symptoms point to something going on in the power supply.  If replacing the PS board does not solve the problem then you must look around for broken grounds, cracked boards,  cold solder joints, etc.

There are a few forums for this set outlining the replacement of certain capacitors in the set.  Have you looked at those?  You can find links with a google search by model number.

Happy hunting/tinkering.  

TV/VCR/Stereo Troubleshooting

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Consumer Electronics of all kinds. Audio, esoteric audio systems and components, video, tv. Digital equipment for consumer use. Ham radio and automotive electronics. Note: I give advice on tv repair based on general consumer electronics engineering experience but I am not engaged in actual repair of sets. MAKE SURE YOU GIVE THE MAKE AND MODEL NUMBER AND AGE OF THE SET. BE SURE TO CHECK YOUR EMAIL FOR THE RETURN ANSWER DURING THE NEXT 24 HOURS AS I TRY TO REPLY TO ALL QUESTIONS WITHIN THE SAME DAY IF NOT THE SAME HOUR.


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